Conventionally, a tampon that is molded into a cylindrical shape by compressing a flat absorbent core has been developed as a menstrual tampon. The cylindrical absorbent core is used in a state of being inserted into a vagina and removed therefrom after use. For this reason, the cylindrical absorbent core is provided with a string-shaped member for removal after use. In addition, some tampons are provided with a cylindrical applicator used for inserting the tampon into a vagina.
A tampon has an absorbent core that is limited in size and area for comfortable insertion into a vagina. Various improvements have been made within such limiting conditions, in order to improve absorptive capacity of the absorbent core.
For example, a cylindrical tampon having a concave portion formed on a surface of an absorbent core, in order to improve the absorptive capacity thereof, has been disclosed (Japanese Unexamined Patent Application Publication No. 2001-8964, hereinafter referred to as Patent Document 1). Since the concave portion is formed on the surface of the absorbent core, menstrual blood is absorbed not only from a surface of the absorbent core, but also by the inside of the absorbent core through the concave portion.
However, in such a tampon, there has been no improvement in deforming the absorbent core into a cylindrical shape, in a step of forming the absorbent core into a cylindrical shape. As a result, various molded products have been manufactured that have a cylindrical shape, although the folded shape of the absorbent core is inconsistent.
In a case where the absorbent cores have inconsistent folded shapes, a string-shaped member for removal of the tampon provided in the absorbent core is disposed at variable positions due to folding of the absorbent core. For example, if the string-shaped member is disposed out of a center (a center of gravity in a cross-section) of the cylindrical absorbent core that is molded into a cylindrical shape, a pulling force applied to the string-shaped member is transmitted to a position out of the center (the center of gravity in a cross-section) of the absorbent core when a user tries to remove the absorbent core. As a result, the absorbent core is inclined inside the vagina and may have given an uncomfortable feeling to a user when the user tries to remove the absorbent core. In addition, if the string-shaped member is disposed to be exposed on a surface of the absorbent core, a liquid such as menstrual blood may have leaked through the string-shaped member.
Furthermore, there are products in which the cylindrically-shaped absorbent core is stored in an applicator formed of a resin. At a tip end of the applicator, a part called petals is formed with radial slits that is deformed and opened by the cylindrical absorbent core so as to insert the cylindrical absorbent core into the vagina. Here, in a case where the string-shaped member of a tampon is disposed on a side face of the cylindrical absorbent core, the petals of the applicator may have contacted the string-shaped member and generated friction against a pulling force.